The Joint Commission of Accreditation of Healthcare Organizations requires that health care organizations implement a set of quality indicators by 1999. However, despite well-documented socioeconomic and racial/ethnic disparities in health care quality, little attention has been given to the quality of care provided to these groups. Any effort to institute a system for monitoring such disparities is hampered by the reluctance on the part of health care delivery and insurance organizations to routinely collect socioeconomic and racial/ethnic data on their patients. Aims: 1) To develop a series of practical, clinically relevant, indicators that are sensitive to differences in quality of care provided to socioeconomically vulnerable populations. 2) To evaluate the performance of census-based indicators as proxies for individual measures of socioeconomic position (SEP). 3) to determine the extent to which socioeconomic measures account for disparities in the quality of care provided to black and Hispanic patients. Methods: Using Medical Expenditure Panel Survey (MEPS) data, we will create a series of Health Plan Employer Data and Information Set (HEDIS) type quality of care indicators including preventive services, access, outcomes, and satisfaction, to assess disparities by quartiles of income and education. In collaboration with AHCPR, we will geocode MEPS subjects addresses to the Census-block level and append a series of census-based indicators of SEP to each observation. We will then compare the performance of census-based SEP indicators with the individual measures (income and education) in accounting for disparities in the HEDIS type indicators. Last, we will examine the extent to which these measures account for observed differences in HEDIS type indicators by race/ethnicity. Significance: This proposal has national policy implications for monitoring and minimizing, socioeconomic and racial/ethnic disparities in health care. First, the project establishes a national baseline from which progress toward reducing such disparities can be monitored through future iterations of MEPS. Second, the project examines the performance of census-derived measures as an unobtrusive and inexpensive way to compile socioeconomic data on patients using existing data. In addition to monitoring disparities in quality of care, socioeconomic data can be used to define the health care needs of enrolled populations, risk adjust provider profiles, and monitor enrollment/disenrollment patterns. Thus, this project has implications for health care quality improvement, accreditation, and policy making.